Brake



V. BENDIX March 14, 1933.

BRAKE Filed Jan. 19, 1928 INVENTO VIIY6WIBWOIX ATTORNEY Patented Mar. 14, 1933 UNITED STATES PATENT OFFICE VINCENT IBENDIX, OF CHICAGO, ILLINOIS, ASSIGNOB. T BENDIX BRAKE COMPANY,

' OF SOUTH BEND, INDIANA, A CORPORATION OF ILLINOIS BRAKE Application filed January 19, 1928. Serial No. 247,798.

This invention relates to brakes, and is illustrated as embodied in a novel internal expanding brake for an automobile. An object of the invention is to provide a ver powerful brake of'the servo type, pre erably fully effective in either direction of drum rotation, of a simple and inexpensive design.

An important feature relates to the operation of anchored friction means, preferably includin a pair of anchored shoes, by means o a servo shoe moving with the drum into direct thrust engagement with one or the other of the shoes. In one very eflicient embodiment, at least one of the anchored shoes, when applied by the servo shoe, is arranged to apply the other anchored shoe. As illustrated, this is accomplished by providing one of the anchored shoes with a thrust portion extending beyond the anchor and operatively engaged by the other shoe.

Other features of novelty relate to providing the servo shoe, or some equivalent shoe, with novel spaced parts guidingly embrac- 2:, ing the end ofv an adjacent shoe, to a novel applying device shown as including a roller having a novel mounting and engaging the edge of the shoe stiffening web, and to other novel and desirable structural features 30 which will be apparent from the following description of the illustrative embodiments shown in the accompanying drawing, in which:

Figure 1 is a vertical section through the 5 brake, just inside the head of the brake drum, showing the shoes in side elevation;

Figure 2 is a partial elevation corresponding to the lower part of Figure 1, and showingza modification; and 40 igure 3 is a section on the line 3-3 of Figure 1, showingthe novel roller mount- The illustrated brake includes a rotatable drum 10, at the open side of which is a support such as a backing plate 12, and within which is arranged the friction means of the brake. I

The novel friction means shown in Figure 1 includes a pair of anchored shoes 14 and 16, the torque of which is taken by a pivot 18 at one side of the drum. Shoe 14, reinforced if desired by welding se aratel formed plates 20 to opposite sides 0 its sti ening web, is pivoted directly on the an chor l8, and preferably has a thrust portion 22 on the opposite side of the anchor from its friction face, which portion has a semicircular bearing embracing a floating pivot 24 engaged by a similar bearing in the end of the shoe 16. A return spring 26 urges the shoes away from the drum and also holds the two shoes against pivot 24. Shoe 16 may also, if desired, be reinforced by separately-formed plates 28 welded to its opposite sides.

It will be seen that if the. brake is applied with the drum turning counter-clockwise, shoe 16 thrusts through pivot 24 in a direction to turn shoe 14 about pivot 18 against the drum. The positions of the shoes 14 and 16, with the brake released, may be determined by suitable stops 30, illustrated substantially as described in application Serial No. 145,189, filed October 30, 1926, by Adiel Y. Dodge. Preferably the shoes 14 and 16, or their equivalents, are applied by means including a novel floating friction servo shoe '32, which may have rounded ends in direct thrust engagement with the rounded ends of shoes 14 and 16. The ends of the stiffening web of shoe 32 are shown with spaced parts, such as separatelyformed plates 34 projection-welded to the sides of the web, which'parts guidingly embrace the ends of shoes 14 and 16.

When the drum is turning clockwise, the servo shoe 32 acts against shoe 14, and when the drum is turning counterclockwise the servo shoe acts against shoe 16. When mounted on an automobile, I prefer that the drum in Figure .1 should turn counterclock wise when the car is movin forward.

The servo shoe 32 is app ied, against the resistance of two return springs 36, by novel means such as-a thrust roller 38 mounted. on a pivot 40. carried by a pair of arms-42 and 44 mounted on an operating shaft 46. Cotter pins 48, or other suitable devices, are provided to hold pivot 40 against axial movement; Washers 50, of larger diameter than roller 38, are mounted on pivot 40 between arms 42 and 14, on opposite sidesof roller 38, and guidinglg' em race. the lower portion of the web of s oe 32. v 1 The web may-be reinforced at this point, if desired, by plates 52 rojection-welded to its sides, the web and p ates '52 having their inner edges ground or otherwise formed on an are engaged by roller38, and which arc preferably has its center arranged (when the psake is applied) at the center of the drum In the arrangement of Figure 2, shoes 114 and 116 are formed at their adjacent ends with semicircular sockets embracing a fixed pivot or anchor 118. In this arrangement the articulation 24 is omitted. v

While two illustrative embodiments have been described in detail, it is not my intention to limit the scope of the invention to those particular embodiments,-or otherwise than-by the terms of the appended claims.

I claim:

1. A brake comprising, in combination, an anchor, a first shoe engaging the anchorand having its friction face on one side of the anchor and having a thrust portion extending on the opposite side of the anchor, a second shoe 'actm on said thrust portion to apply the first s 0e, and servo friction means for actuating the second shoe.

2. A brake comprising a pair of shoesarranged end to end and having alined stifiening webs in direct thrust enga ement with each other, and one of whic shoes has spaced :parts carried b and projecting be- 'ond the end of its sti ening web and guidand) having parts guidingly embracing said we 8. A brake-applying device including a pair ofspaced arms carrying a pivot and a thrust roller mounted on the pivot between said arms. v 9. A brake-applying device including a pair of spaced arms carrying a pivot, a thrust roller mounted on the pivot between said arms, and a pair of guide washers of greater diameter than the roller mounted on the pivot between said arms on opposite sides of the roller.

10. A brake comprising, in combination, an anchor, a first shoe engaging the anchor and having its friction face'on one side of the anchor and having a thrust portion extending on the opposite side of the anchor, and a second shoe acting on said thrust portion to apply the first shoe.

.11. A brake comprising, in combination, an anchor, a first shoe engaging theanchor and having its friction face on one side of the anchor and having a thrust portion extending on the opposite side of the anchor, means acting on said thrust portion to applythe first shoe, and servo friction means for actuating said means.

In testimony whereof, I have hereunto signedmy name.

VINCENT BENDIX.

mgly embracing the web of the other shoe. 7

3. A brake comprising a pair of shoes arranged end to on including alined stifi'ening webs havin direct thrust engagement and one of whic shoes has spaced separately-formed plates secured to and pro ecting beyond the end of its stiffenin web and gliliidingly embracing the webv o the other e 00.

4. A brake including three shoes arran ed endto end. and formed with alined sti ening webs at least .at'their adjacent ends, the

50 web of one of the shoes having direct thrust enga ement with the webs on the other shoes an havin spaced parts guidingly embracing the ot erpshoes. 5'. A brake shoe having at both ends pairs of separately-formed plates secured thereto to form spa'ced projecting arms.

6. A brake comprising a shoe having Y a stifie'ning" web, in combination with an applying'roller operatively engaging the edge 1 of sa-ld web andhavingparts projecting at opposite sides of the roller and em racing said web. v

7.- A brake comprising a shoe having a stifienin web, in combination with an ap-' 65 plying evice 'operatively engaging said web guidingly 

